Creation Of Free Radicals Research Articles

Utility of Perl's Prussian Blue Stain in Exfoliated Buccal Cells of Thalassemia and Sickle Cell Anemia Patients and Their Correlation With Serum Ferritin Levels.

Introduction Iron is essential for all living beings. Excess iron, on the other hand, is dangerous because it causes the creation of free radicals. As a result, iron absorption is carefully managed to maintain a balance between absorption and iron loss in the body. Due to the lack of particular excretory channels for iron in humans, iron excess in the tissues is common. It can be caused by a number of factors, including increased iron absorption, as seen in hemochromatosis, or frequent parenteral iron treatment, as seen in thalassemia and sickle cell anemia patients (a transfusional overload). Aim The study aims to demonstrate Perl's Prussian blue stain to identify iron overload at a preliminary stage and correlate with serum ferritin levels in patients withthalassemia and sickle cell anemia who frequently receive blood transfusions. Materials and methods The present study comprised 62 confirmed cases of thalassemia and sickle cell anemia patients undergoing repeated blood transfusions of a minimum of 15/more, along with 62 clinically healthy individuals between December 2016 and November 2018. The patients with thalassemia and sickle cell anemia were confirmed by hemoglobin electrophoresis (Bio-Rad D-10, Bio-Rad Laboratories, Inc, California, United States). The buccal smears were obtained from these patients along with the controls, and these slides were stained by Perl's Prussian blue stain and were examined under a light microscope. Results Sixty-two cases and 62 controls were considered in the current investigation. Forty-seven of the 62 people had thalassemia, and 15 had sickle cell anemia. Thirty-nine out of the 47 patients with thalassemia and six of the 15 individuals with sickle cell anemia had positive results for Perl's Prussian blue stain. All patients had elevated blood ferritin levels, with varying ranges associated with positive results for Perl's Prussian blue stain. Conclusion The objective of this study was to demonstrate the utility of oral exfoliative cytology in thalassemia and sickle cell anemia patients who often receive blood transfusions as a screening and diagnostic tool. The exfoliative cytology methods' acceptability and simplicity, along with their correlation with serum ferritin levels and Perl's Prussian blue reaction, make this noninvasive procedure an excellent screening and diagnostic tool for all patients who receive repeated blood transfusions.

Ferulic Acid: Signaling Pathways in Aging.

The need for clinical remedies to the multiple age-related deficiencies in skin function brought on by extrinsic and intrinsic causes is increased by these demographic changes. Reactive oxygen species (ROS), mitochondrial deoxyribonucleic acid (mtDNA) mutations, telomere shortening, as well as other factors, contribute to the aging of the skin. In this overview, the issue of human skin aging is introduced, along with several pathways and the protective effects of ferulic acid in light of current patents. The complex antioxidant effect of ferulic acid depends on the "sweeping" away of free radicals as well as the suppression of the synthesis of ROS or nitrogen. Furthermore, Cu (II) or Fe protonated metal ions are chelated by this acid (II). Ferulic acid is a free radical scavenger as well as an enzyme inhibitor, increasing the activity of enzymes that scavenge free radicals while decreasing the activity of enzymes that speed up the creation of free radicals. AMPK signalling, which can regulate cellular homeostasis, stress tolerance, cell survival and proliferation, cell death, and autophagy, has recently been linked to aging and lifespan. Therefore, Caenorhabditis elegans (C. elegans) and rodents had longer life-spans due to specific AMPK activation. By inhibiting the TGF-β/Smad signalling pathway, UV irradiation can reduce the production of procollagen. Glycation changes the skin's physical characteristics, making it less elastic and stiffer. . Excessive free radicals simultaneously trigger the nuclear factor kappa B (NF- κB) signalling pathway, increasing TNF levels and matrix metalloproteinase production (MMPs).

Effects of nonthermal physical processing technologies on functional, structural properties and digestibility of food protein: A review

AbstractThis review assesses the nonthermal physical processing technologies for protein modification. The review also discusses the structural, functional, and digestibility attributes of protein following nonthermal physical processing. Applications of ultrasonication, ultrahigh pressure, and pulsed electric field (PEF) can induce the conformational changes of protein via the creation of free radicals and/or larger/smaller protein molecules, damaging the primary, secondary, tertiary, and quaternary structure of protein, and thus influence the functional properties. Some key achievements in using nonthermal physical technologies to process protein‐rich foods include improved enzymatic hydrolysis, solubility, emulsification, foaming, gelatinization, digestion properties, and reduced allergenicity. Therefore, nonthermal physical technologies are useful methods to modify food protein structure and functionality for the food industry.Practical ApplicationThe demand for protein with desirable functional properties and nutritional value makes it imperative to find suitable processing technologies that could conserve or yield high quality proteins from both conventional and nonconventional sources. Since thermal processing (including microwave, radiofrequency heating, etc.) could possibly reduce the quality attributes of proteins, many researchers have focused their investigations on nonthermal physical processing to improve the functional properties of proteins. To this regard, this review discusses nonthermal techniques, including ultrasonication, high‐pressure processing, PEFs, cold plasma, and ultraviolet.

Comparative study of biological activities of different extracts of root and whole plant materials of Ajuga bracteosa from Bhimber Azad Kashmir Pakistan

Ajuga bracteosa is native to Himalayan region, Afghanistan, China and Malaysia. People of northern areas of Pakistan call it ‘korri booti’ as it has bitter taste. Ajuga bracteosa is ethnically used against malarial fever, diabetes, cancer, and sore throat. The theme of present work was to appraise the biological significance of Ajuga bracteosa through in vitro studies. n-Hexane, chloroform, and methanol extracts of root and whole plant materials were obtained via maceration. Qualitative and quantitative analysis of phytochemical constituents was done. The antioxidant potency was judged by DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS (2,2-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) free radical scavenging assays. Antimicrobial efficacy was assessed by agar disc diffusion method. Phytochemical review confirmed the existence of flavonoids, saponins, phenols, tannins, terpenoids, xanthoproteins, carbohydrates, and glycosides. Total flavonoid and total phenolic contents were shown as rutin and gallic acid equivalents respectively. Root extracts gave more significant results of DPPH and ABTS potential (100 % and 92 % respectively) as compared to whole plant extracts (90 % and 75 % respectively). A. bracteosa is a plentiful source of polyphenolic compounds. Polyphenolic compounds are thought as natural antioxidants because of their ability of hydrogen atom donation and presence as stable radical intermediates preventing further creation of free radicals in the body. Root extracts showed greater resistance against pathogens as compared to extracts of whole plant material. Keywords: Antimicrobial activity; Antioxidant activity; Medicinal plants; Phytochemical screening http://dx.doi.org/10.19045/bspab.2021.100135

Effect of 80 MeV O6+ ion irradiation on structural, morphological, dielectric, and ferroelectric properties of (1-x)PVDF/(x)BaTiO3 nanocomposites

The polyvinylidene fluoride/barium titanate (1-x)PVDF/(x)BaTiO3 nanocomposite films (x = 0.2 and 0.5) were prepared by solution mixing method. The dielectric constant (e′) was increased by the BaTiO3 incorporation in the PVDF matrix. The pristine PVDF and nanocomposite films were uniformly irradiated with 80 MeV O6+ ion beam over an area of 1 cm2 at room temperature under the high vacuum of ~ 5 × 10−6 Torr with ion fluences, 5 × 1010, 2 × 1011, and 2 × 1012 ions/cm2. After irradiation, recrystallization and α→β phase transition were observed in PVDF through X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy analysis. However, almost complete amorphization was observed in BaTiO3 filler in (1-x)PVDF/(x)BaTiO3 nanocomposite samples. After irradiation, the dielectric constant (e′) increases at lower fluence (5 × 1010 ions/cm2) while decreases at higher fluence (2 × 1012 ions/cm2) as compared with the pristine samples. The creation of free radicals in PVDF due to chain scission and crosslinking observed upon irradiation is responsible for the observed behavior of dielectric constant (e′). While in nanocomposites, the change in the dielectric properties of BaTiO3 in nanocomposites samples after irradiation can be associated with the radiation-induced amorphization of BaTiO3. After irradiation, both the remanence polarization and coercive field increase for PVDF while decrease for nanocomposite samples. The observation of amorphousity in BaTiO3 phase through swift heavy ion irradiation is interesting and important from a fundamental point of view.

Chemical dynamics characteristics of Kapton polyimide damaged by electron beam irradiation

Polyimides, particularly poly-(pyromellitic dianhydride-4,40-oxydianiline) or PMDA-ODA (Kapton-H®), are ubiquitous in the aircraft and aerospace industries, flexible printed circuits, and many other high-performance applications. For many of these applications, the polymer's stability during and after radiation damage is a serious concern. The effect of electron irradiation on the breaking of inter-molecular bonds and creation of free radicals in Kapton polyimide were studied using reactive molecular dynamics simulation with the polarizable ReaxFF method and experimentally on pristine and electron irradiated polyimide by vibrational spectroscopy, electron paramagnetic resonance, nuclear magnetic resonance, wide angle x-ray diffraction, small angle x-ray scattering, and dynamic mechanical analysis. In our simulations, the electron beam is approximated by a dense column of negatively charged particles, which is inserted at random positions in the polyimide matrix. In order to observe inter-molecular bond breaking during the time frame of the molecular simulations, each electron beam is switched on for 2 fs, causing an average energy of 21 eV per electron trajectory to be transferred to the polyimide through Coulomb interactions during the simulation. Experimentally, polyimide is aged in vacuum with a 90 keV electron beam with a maximum penetration depth greater than the material's thickness.Throughout the simulations, modifications in the chemical structure of the polyimide during and after the electron beam irradiations are monitored. During electron beam irradiation, hydrogen atoms separate from different parts of the polyimide through C–H bond cleavage. After turning off the electron beams and running a microcanonical molecular dynamics simulation for 0.5 ns, several chemical and structural rearrangements are observed in the polyimide structure. The chemical modifications mostly include ring opening and other changes to the imide rings. The computations are compared to infrared spectroscopy, electron paramagnetic resonance, nuclear magnetic resonance, x-ray scattering, and mechanical measurements on aged and pristine polyimide to both guide and validate the conclusions from the computational study. Apart from these changes in chemistry we also evaluate temperature evolution and change in mechanical response of the polyimide slab caused by electron beam exposure. Taken together, the direct measurements of the electronic, chemical, and mechanical properties of the irradiated Kapton films validate the key results of the model.

Structural and optical properties improvements of PVP/gelatin blends induced by neutron irradiation

Blends of polyvinylpyrrolidone and gelatin were prepared in three different concentrations to study the modifications in their structural and optical properties induced by neutron irradiations with different neutron fluence values from ~ 108 up to ~ 1011 neutron/cm2. X-ray spectroscopy revealed that the irradiation has induced a recrystallization phenomenon in the studied blends and the crystallinity index increased by increasing the neutron fluence due to the breaking of the crystallites. Fourier-transform infrared spectroscopy came to confirm the existence of interactions between interchain groups and a higher compatibility for the irradiated blends. The irradiation induced defects inside the material were responsible for the change in their optical and structural properties. The creation of free radicals or ions inside the conduction bands has led to the increase in the number of carriers on localized states; this has caused the increase in optical conductivity of the irradiated blends as a result of decreasing the energy gaps by increasing the neutron fluence. Results may widen the applications of the gelatin based blends to include optoelectronic devices, organic light emitting devices, solar selective and anti-reflectance bio-coatings, optical organic glass and lenses.

Hydroxyl radical formation in batch and continuous flow ultrasonic systems

The creation of free radicals by ultrasonic cavitation is the main mechanism that leads to chemical degradation of target pollutants and the process is considered an alternative advanced oxidation technology. The goal of this study was to compare the effects of batch and continuous flow ultrasonic systems on the formation of hydroxyl radicals. Ultrasonic batch experiments were conducted in two reactors (small and large) using a standard 20kHz catenoidal titanium horn at varying amplitudes and sonication times. The effect of saturating gas was also investigated by introducing helium and air at 1Lmin−1 into the larger 100mL reactor. In the continuous flow system, the experiments were conducted with a 20kHz, 3.3kW ultrasonic systems using a titanium “donut” horn at varying volumetric flow rates and amplitudes. Formation of hydroxyl radicals was determined using terephthalic acid dosimetry measurements. At the same energy densities, higher hydroxyl radical concentrations were formed in the batch system than in the continuous flow system. Sonication time appeared to be the main factor that influenced the results in batch and continuous flow systems. The two gases (helium and air) did not increase the hydroxyl radical formation at any amplitude or sonication time tested.

Free radical capacity in plasma of type 2 diabetic patients

Type 2 diabetes is most common in middle age. This type of diabetes usually causes defects in insulin secretion. The disease worldwide is increasing day by day. The creation of free radicals that can occur in patients with diabetes on protein oxidation, lipid peroxidation; DNA can affect and damage the cells. The kidneys, eyes, cardiovascular system, blood vessels are so detrimental. This study aims to evaluate free radical capacity in plasma of type 2 diabetic Patients. This case - control study was conducted using random sampling. A survey was carried out on blood from samples, which included 30 type 2 diabetic patients, and 30-control sample of age and sex matched subjects. The free radical capacity level were significantly (P = 0.005) higher in control sample compared with type 2 diabetic patients. Free radicals have an important part in reducing cellular damage.

Au-nanoparticles grafted on plasma treated PE

Polyethylene (PE) surface was treated with Ar plasma. Activated surface was grafted from methanol solution of 1,2-ethanedithiol. Then the sample was immersed into freshly prepared colloid solution of Au-nanoparticles. Finally Au layer was sputtered on the samples. Properties of the modified PE were studied using various methods: AFM, EPR, RBS and nanoindentation. It was shown that the plasma treatment results in degradation of polymer chain (AFM) and creation of free radicals by EPR. After grafting with dithiol, the concentration of free radicals declines. The presence of Au and S in the surface layer after the coating with Au-nanoparticles was proved by RBS. Plasma treatment changes PE surface morphology and increases surface roughness, too. Another significant change in surface morphology and roughness was observed after deposition of Au-nanoparticles. Nanoindentation measurements show that the grafting with Au-nanoparticles increases adhesion of subsequently sputtered Au layer.

Ion beam cancer therapy: Fundamental aspects of the problem

We discuss different physical processes which may be responsible for biological damage induced by an ion beam propagating through living tissue. The creation of free radicals and an electron plasma, dissociative attachment of low-energy electrons, and local heating mechanisms are considered. Numerical estimates are performed for the case of carbon ion beams. We conclude that all three mechanisms are capable of inflicting single and double strand breaks in DNA molecules and thus can be responsible for the observed enhanced biological effectiveness of ion beams in cancer therapy.

Mind and energy metabolism

Protein is an essential component of human diet and can be applied to many aspects in food systems due to its abundant nutritional value and functional properties. There are many physical methods that have been used to modify the inherent structure of protein to expand its application areas in the food industry. Among them, electric fields and electromagnetic wave technologies have attracted increasing attention on their abilities to modify food protein structure and functionality, due to the advantages of energy efficiency, food safety and minimal loss of nutrients.The current review presents the effects of electric fields and electromagnetic wave including pulsed electric field, microwave, radio frequency and gamma irradiation on the changes in food protein structure (primary, secondary, tertiary and quaternary) and functionality (solubility, apparent viscosity, emulsifying, foaming, and gelling properties). The affecting factors such as protein concentration and pH, and the strength and duration of electric fields and electromagnetic wave on the mechanisms and effectiveness of changes in protein structure and functional properties are introduced, and the advantages and limitations of these technologies for protein modification are also discussed.Applications of electric fields and electromagnetic wave can induce the conformational changes of protein via the creation of free radicals or larger or smaller molecules, damaging the primary, secondary, tertiary and quaternary structure of protein, and thus influence the functional properties. Therefore electric fields and electromagnetic wave are useful methods to modify food protein structure and functionality for the food industry, and active researches focus on multi-technology corporations for modifying protein structure are urgently required.

Integrated Sun Protection Factor: A New Sun Protection Factor Based on Free Radicals Generated by UV Irradiation

The present work uses the initial step of the whole cascade of biological effects in the skin, the creation of free radicals by means of UVA/UVB radiation, to develop a total sun protection factor. Until now, existing in vivo indices have not been fully satisfying: SPF only reflects protection from UVB light, and persistent pigment darkening is restricted to the UVA part of the sun spectrum. The quantitative measurement of free radicals generated in human skin biopsies by means of electron spin resonance X-band spectroscopy allows to determine a new total SPF. This new sun protection index covers all UVA/UVB wavelengths taking into account their effects in the epidermis as well as the dermis. Use of skin biopsies avoids exposure of human volunteers to potentially harmful radiations. The new index is always practically equal or lower than the in vivo SPF depending on the level of a product’s UVA/UVB photoprotection balance. With this, we propose to name this new protection index ‘integrated sun protection factor’.

Study of effects in polyethylene terephthalate films induced by high energy Ar ion irradiation

Semicrystalline polyethylene terephthalate (PET) foil stacks were irradiated with 1.373 GeV Ar ions to different fluences ranging from 1.0×10 10 to 5.0×10 12 ions/cm 2. The induced effects were investigated by means of the Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible absorption spectroscopy (UV/VIS) and electron spin resonance spectroscopy (ESR). FTIR measurements show that bond breaking processes are mainly observed at the ethylene glycol residue of trans configuration and at the para position of benzene rings above a critical dose of about 4.0 MGy. Damage cross-section has been extracted for the band at 973 cm −1 from the dependence of the absorbance on fluence and it shows a linear dependence on the mean electronic energy loss. UV/VIS measurements show a strong increase in absorbance in the ultraviolet and visible regions. It is found that for the same absorbed dose, more increase in absorbance is induced at higher electronic energy loss. ESR measurements indicate the creation of free radicals. The radical concentration is found to increase rapidly with the increasing absorbed dose above 4.0 MGy.

Neuroleptic-induced striatal damage in rats: a study of antioxidant treatment using accelerometric and immunocytochemical methods.

Investigators have postulated that neuroleptic medications may affect the motor system through the creation of free radicals. Also, structural brain changes related to oxidative damage may disrupt normal striatal function. The goals of this study were to examine whether an antioxidant diet reduced the abnormal movements caused by long-term neuroleptic exposure and to examine structural effects within specific striatal regions in rats. Rats were given a basal diet or a diet high in antioxidants for 4 months, and treated with 10 mg/kg fluphenazine decanoate or sesame seed oil IM every 2 weeks. At baseline and after treatment, head movements were quantified by accelerometry, and immunocytochemically stained cholinergic neurons in the ventrolateral, mediodorsal, and ventromedial regions of the striatum were quantified. Rats treated with fluphenazine had significantly lower neuron densities than those that did not receive antioxidants. Rats exposed to a diet consisting of antioxidants had significantly higher neuron densities than those that did not receive antioxidants in each of the three regions tested. Rats treated with fluphenazine had a greater increase in the number of accelerometric peaks recorded per minute compared with untreated animals. The increase in the number of accelerometric peaks recorded per minute was lower for animals exposed to antioxidant diets compared with unexposed animals. Lastly, there was a significant correlation between the accelerometric peak change score and cholinergic neuron density in all three regions. Our results suggest that long-term neuroleptic treatment is associated with an increase in head movements and a reduction in ChAT-stained striatal cholinergic neurons and that these abnormalities are reduced by antioxidants.

High-field induced electrical aging in polypropylene films

According to Kao’s model of electrical discharge and breakdown in condensed insulating materials, charge carrier injection from electrical contacts and subsequent dissociative trapping, and recombination play a decisive role in the breaking of polymer chains and the creation of free radicals or low-weight molecules, and hence traps. We believe that electrical aging is due to this gradual degradation process. The increase in structural degradation and trap concentration reflects the degree of electrical aging and hence the lifetime of the electrically stressed polymers. On the basis of this concept, we have derived a theoretical formula for the prediction of the lifetime of insulating polymers. We have also carried out experiments on polypropylene films at high electric fields. It is found that destructive breakdown occurs when the accumulation of field induced traps reaches a certain critical value. Experimental results are in good agreement with our theoretical model.

Detection of energetic heavy ions

The delta-ray theory of track structure, applied earlier to such 1-or-more hit detection systems as the inactivation of dry enzymes and viruses, the NaI(Tl) scintillation counter, and nuclear emulsion, is extended to the silver activated phosphate glass dosimeter, the LiF thermoluminiscent dosimeter, the creation of free radicals in solid biological substances, solid and liquid organic scintillators, and the ferrous sulfate (Fricke) dosimeter. The response of these systems to both gamma-rays and heavy ions is characterized by two parameters: 1) D γ 37, the dose of gamma-rays at which 37% of the sensitive elements remain unaffected by the radiation, and 2) a 0, the physical radius (or the exciton diffusion length, or the range of short-range order) of the sensitive element. The decline of detector response with increase in the stopping power of the bombarding ion, and the non-linearity of the detector response are characteristic properties of 1-hit detectors, and are most pronounced for the most sensitive detectors. Explicit information about the cross-sectional area of the sensitive target cannot be gained from measurement of the activation cross-section as a function of the stopping power of the incident ion, for there is no saturation cross-section for 1-hit detectors. Since parameters describing the incident ion and those describing the detector are not separable variables, the response of a detector cannot be described through a product of two factors, one containing only ion parameters and representing “radiation quality”, and the other containing only detector parameters and representing “detector quality”.

Creation of free radicals in highly diluted gas-reactions

Creation of free radicals in highly diluted gas-reactions